Process of making acid dyes of the anthracene series.



UNITE STATES MICHAEL ILJ'INSKY, UERDINGEN, GERMANY, ASSIGNOR TO THE FIRMOF R. WEDE-.

KIND & CO. M. B. 1-1., OF UERDINGEN, GERMANY.

No Drawing.

To all whom it may concern:

Be it known that I, MICHAEL ILJINsKY,

a subject of the Czar of Russia, and residing at Uerdingen-on-the-Rhine,Germany,

have'invented a certain new and useful Process for Making Acid Dyes ofthe Anthracene Series, of which the following is a specification. p

Anthrafiavic acid has hitherto not been employed for condensations witharomatic amins in the manufacture of dye-stuffs. Although theintroduction of amin residues into oxyanthraquinones has been suggestedin a general way, the only oxyanthraquinones specifically mentioned ashaving been successfully employed in the process, are: chinizarin,purpurin, oxyanthrapurpurin, oxyflavopurpurin, anthrachryson,alizarinbordeaux, aliza'rin-pentacyanin, alizarinhexacyanin,hexaoxyanthraquinone. In other processes by which variousoxyanthraquinone derivatives are combined with aromatic amins, nomention is made of dyes which have anthrafiavic acid as a startingmaterial, nor ofarithraflavic acid itself, nor of its derivatives.

' My researches have disclosed that many derivatives of anthraflavicacid are 'extremely well adapted, under various conditions, to becombined with aromatic amins, and that the products of condensationobtained in the process yield exceedingly valuable brown, brownredviolet-red, blue and blue-green acid dyes. Suitable anthraflavinderivatives for this purpose are:

(A) Dinitrodisulfoanthrafiavic acid, made by sulfonating anthraflavicacid w ithout theaddition of boric acid and thereafter nitrating thesulfonated product. According to Dr. Adolf WintherNZusammenstellung derPatent/e auf elem Gebz'ete der 0rgam'sclwn Uhemie, Vol. II, page 659,the product has probably the structural for- The same sulfonated withthe addi-' Specification of Letters Patent. Patented J ine Applicationfiled June 22, 1910. Serial No. 568,349.

tion" of mercury, in the presence or absence of boric acid, and thennitrated. The struc tural formula of this compound is not'yet exactlyknown, the SO H groups are probably in the a position.

(D) Nitrated products of the dichloranthrafiavinsulfonic acids made bychlorinat inganthrafiavic acid in the presence of an alkali, by then.sulfonating the product formed with or without the addition of boricacid, and by finally nitrating thechlorinated and sulfonated product.The

structural formulae of these products are still .unknown' Thecondensation preferably takes place in the presence of the hydrochlorideof the. corresponding aromatic amins. Very favorable results with thedichloranthraflavinsulfonic acids are a.

effected by the simultaneous use of sulfur, sodium-sulfid and aromaticamins. The nitrated anthraflavinsulfonic acids give darkblue dye-stuffs;the chloratedproducts are suitedfor the production of brown dyes, Thefollowing examples show-the man-' ner of working: I is 1. 10 parts ofthe potassiums'alt of the dinitrodisulfoanthrafiavic acid (made bysulfonating anthrafiavic acid in the presence of boric acid and byfollowing nitrating), 5 parts of .muriatic anilin, 50 parts anilin, areheated for about ,6 hours to from 140 to 145 C. in a vessel equippedwith a return-cooler. The product of condensation is then freed from theanilin which has not been reacted upon, by either distilling off theanilin with steam after the contents of the vessel have been madealkaline, or by extracting from the product of condensation the anilinwith a dilute solution of muriatic acid. In the former case the productfreed from anilin, is separated by filtration into an alkali-insolubleand an alkali-soluble part. By acidulating and subsequent filtrating,the latter is divided into a watersoluble and a water-insoluble portion,which is however soluble in alkali and which remains on the filter,while the water-soluble dye-stuff vis precipitatedirom the solution bymeans of salt. In case the excess anilin has been extracted with acidand by subse- 'quent filtration, the residue is separated into awater-soluble, an alkali-soluble and an insoluble part in a similarmanner. The alkali-soluble part of the product yields a water solubleblue-red powder, which dyes parent. 3 5

unmordanted or mordanted wool violet. By

subsequent chromating with bichromate, a

addition of anilin salt, quite similar results. are obtained by asufliciently long-continued heating.

2. 10 parts of nitrated dichloranthraflavinsulfonic acid, 2 parts ofsulfur, 4: parts of crystallized sodium-sulfid, 50 parts of anilin, areheated for two hours in a vessel with a return-cooler at from 125 to 130C. The alkali-soluble part of the product dyes prechromated, orun-mordanted wool or the latter subsequently treated with bichromate, apure brown shade,.which, even with the unmordanted wool, answers themost exacting demands as to fastness.

3. 10 parts of nitrated dichloranthraflavin sulfonic acid, 2 parts ofsulfur, 4 parts of sodium-sulfid, 50 parts of p-toluidin are heated at110 C. for 2 hours. The alkalisoluble part of the product dyes woolsimilar to that of Example 2, a permanent olivebrown-shade.

From the examples cited, not only the great facility of the derivativesof the anv thraflavic acid to react with the aromatic amins, but alsothe great variety of the dyestufis produced by the process becomesapacid is exceeding surprising, and it was not to be forseen in view ofthe rigid symmetri- This property of the anthraflavic' formed bysulfonating and nitrating anthraflavic {acid, with aromatic amins,substan-- tiallyas described.

2. Inthe process of producing acid dyes, the condensation ofanthraflavin derivatives, formed by sulfonating and nitratinganthraflavic acid, with aromatic amins in the resence of meansofcondensation, substantlally as described.

3. In the process of producing acid dyes, the condensation ofanth'rafiavin derivatives,

formed; by .sulfonatin'g and nitrating anthraflavic acid, with aromaticamins in the presence of means of condensation, and the followingseparation of the products formed into water-soluble and alkali-solubledye stufis and an alkali-insoluble part, substantially gas described.

' 4. In the process of producing acid dyes, the condensation of nitratedderivatives of dichloranthraflavin-sulfonic acid with aromatic amins inthe presence of sulfur and sodium-sulfid, substantially as described.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses. i Y

MICHAEL ILJINSKY.

Witnesses:

HENRY AUADPLIEG,

ELISE KALBURCH.

